scholarly journals Solar activity and the mean global temperature

2009 ◽  
Vol 4 (1) ◽  
pp. 014006 ◽  
Author(s):  
A D Erlykin ◽  
T Sloan ◽  
A W Wolfendale
Keyword(s):  
Solar Activity ◽  
Global Temperature ◽  
The Mean

scholarly journals Solar Activity and Global Temperature

1994 ◽  
Vol 143 ◽  
pp. 339-347 ◽  
Author(s):  
Eigil Friis-Christensen ◽  
Knud Lassen
Keyword(s):  
Solar Activity ◽  
Solar Cycle ◽  
Sunspot Number ◽  
Cycle Length ◽  
Global Temperature ◽  
Energy Output ◽  
Temperature Record ◽  
Reconstructed Temperature ◽  
Solar Cycle Length

A major problem in the determination of the magnitude of a possible solar effect on climate is that no physical parameter of solar energy output exists that has been observed long enough to be used for long-term analyses. Therefore, a number of indirect parameters have been proposed, with the sunspot number as the most commonly used parameter. Recently it has been suggested that climatic effects may be more directly associated with the length of the solar cycle. Whereas the magnitude of the sunspot number is only believed to be reliable back to 1750, determination of solar activity minima may be based on other types of data. A recent reconstructed series of solar cycle lengths back to 1500 gives new information about solar activity in particular before and during the Maunder Minimum. A comparison with reconstructed temperature records has revealed that the good agreement between the solar cycle length and the global temperature found for the modern instrumental temperature record is also characteristic for the total series of reconstructed temperature data. A further result is that the response of the temperature during the pre-instrumental era is the same as for the modern temperature record. This finding confirms the close association beween terrestrial temperature and solar activity measured in terms of the solar cycle length.

scholarly journals Grand Minima of Solar Activity and the Mean-Field Dynamo

Solar Physics ◽  
2008 ◽  
Vol 254 (2) ◽  
pp. 345-355 ◽  
Author(s):  
I. G. Usoskin ◽  
D. Sokoloff ◽  
D. Moss
Keyword(s):  
Solar Activity ◽  
Mean Field ◽  
The Mean ◽  
Mean Field Dynamo ◽  
Grand Minima

Solar activity variations and global temperature

Energy ◽  
1993 ◽  
Vol 18 (12) ◽  
pp. 1273-1284 ◽  
Author(s):  
Eigil Friis-Christensen
Keyword(s):  
Solar Activity ◽  
Global Temperature

scholarly journals Ionosperic anomaly due to seismic activities – Part 1: Calibration of the VLF signal of VTX 18.2 KHz station from Kolkata and deviation during seismic events

2009 ◽  
Vol 9 (4) ◽  
pp. 1403-1408 ◽  
Author(s):  
S. Sasmal ◽  
S. K. Chakrabarti
Keyword(s):  
Solar Activity ◽  
Calibration Curve ◽  
Solar Minimum ◽  
Seismic Event ◽  
Space Physics ◽  
Seismic Events ◽  
The Sun ◽  
Reference Signals ◽  
The Mean ◽  
Indian Centre

Abstract. VLF signals are long thought to give away important information about the lithosphere-ionosphere coupling. In order to establish co-relations, if any, between the ionospheric activities and the earthquakes, we need to understand what the reference signals are, throughout the year. The best opportunity to do this is during the period of solar minimum where the number of flares and sunspots are negligible and the data would be primarily affected by the sun and variation would be due to normal sunset and sunrise effects. In this paper, we present the result of the sunrise and sunset terminators as a function of the day of the year for a period of four years, viz, 2005–2008 when the solar activity was very low. The terminators are for the 18.2 KHz VTX signal of the Indian Navy as observed from Indian Centre for Space Physics receiving station located in Kolkata. A total of 624 days of data have been used to obtain the mean plot. Any deviation of observations from this so-called the standardized calibration curve would point to influences by terrestrial (such as earthquakes) and extra-terrestrial events (such as solar activities). We present examples of deviations which occur in a period of 16 months and show that the correlation with seismic events is significant and typically the highest deviation takes place up to a couple of days prior to the seismic event. Simultaneous observations of such deviations from more than one station could improve the predictability of earthquakes.

scholarly journals Influence of the Schwabe/Hale solar cycles on climate change during the Maunder Minimum

2009 ◽  
Vol 5 (S264) ◽  
pp. 427-433 ◽  
Author(s):  
Hiroko Miyahara ◽  
Yusuke Yokoyama ◽  
Yasuhiko T. Yamaguchi
Keyword(s):  
Climate Change ◽  
Solar Activity ◽  
Cosmic Rays ◽  
Cosmic Ray ◽  
Maunder Minimum ◽  
Activity Level ◽  
Solar Cycles ◽  
Early Medieval ◽  
Maximum Period ◽  
The Mean

AbstractWe have examined the variation of carbon-14 content in annual tree rings, and investigated the transitions of the characteristics of the Schwabe/Hale (11-year/22-year) solar and cosmic-ray cycles during the last 1200 years, focusing mainly on the Maunder and Spoerer minima and the early Medieval Maximum Period. It has been revealed that the mean length of the Schwabe/Hale cycles changes associated with the centennial-scale variation of solar activity level. The mean length of Schwabe cycle had been ~14 years during the Maunder Minimum, while it was ~9 years during the early Medieval Maximum Period. We have also found that climate proxy record shows cyclic variations similar to stretching/shortening Schwabe/Hale solar cycles in time, suggesting that both Schwabe and Hale solar cycles are playing important role in climate change. In this paper, we review the nature of Schwabe and Hale cycles of solar activity and cosmic-ray flux during the Maunder Minimum and their possible influence on climate change. We suggest that the Hale cycle of cosmic rays are amplified during the grand solar minima and thus the influence of cosmic rays on climate change is prominently recognizable during such periods.

scholarly journals Can irregularities of solar proxies help understand quasi-biennial solar variations?

2014 ◽  
Vol 21 (4) ◽  
pp. 797-813 ◽  
Author(s):  
A. Shapoval ◽  
J. L. Le Mouël ◽  
M. Shnirman ◽  
V. Courtillot
Keyword(s):  
Solar Activity ◽  
Solar Cycle ◽  
Mean Amplitude ◽  
Embedding Dimension ◽  
Sliding Windows ◽  
Irregularity Index ◽  
Daily Series ◽  
Poissonian Noise ◽  
The Mean ◽  
R Value

Abstract. We define, calculate and analyze irregularity indices λISSN of daily series of the International Sunspot Number ISSN as a function of increasing smoothing from N = 162 to 648 days. The irregularity indices λ are computed within 4-year sliding windows, with embedding dimensions m = 1 and 2. λISSN displays Schwabe cycles with ~5.5-year variations ("half Schwabe variations" HSV). The mean of λISSN undergoes a downward step and the amplitude of its variations strongly decreases around 1930. We observe changes in the ratio R of the mean amplitude of λ peaks at solar cycle minima with respect to peaks at solar maxima as a function of date, embedding dimension and, importantly, smoothing parameter N. We identify two distinct regimes, called Q1 and Q2, defined mainly by the evolution of R as a function of N: Q1, with increasing HSV behavior and R value as N is increased, occurs before 1915–1930; and Q2, with decreasing HSV behavior and R value as N is increased, occurs after ~1975. We attempt to account for these observations with an autoregressive (order 1) model with Poissonian noise and a mean modulated by two sine waves of periods T1 and T2 (T1 = 11 years, and intermediate T2 is tuned to mimic quasi-biennial oscillations QBO). The model can generate both Q1 and Q2 regimes. When m = 1, HSV appears in the absence of T2 variations. When m = 2, Q1 occurs when T2 variations are present, whereas Q2 occurs when T2 variations are suppressed. We propose that the HSV behavior of the irregularity index of ISSN may be linked to the presence of strong QBO before 1915–1930, a transition and their disappearance around 1975, corresponding to a change in regime of solar activity.

scholarly journals Analysis of Ionospheric foF2 by Solar Activity over the Korean Peninsula

2016 ◽  
Vol 6 (1) ◽  
pp. 71
Author(s):  
Min-Ho Jeon ◽  
Chang-Heon Oh
Keyword(s):  
Solar Activity ◽  
Standard Deviation ◽  
Sea Level ◽  
Critical Frequency ◽  
High Electron ◽  
High Electron Density ◽  
Layer Height ◽  
Annual Variations ◽  
F Region ◽  
The Mean

The F2 layer is the upper sector of the ionospheric F region, and it is ~250 km above sea level. It has a high electron density and thus plays an important role in shortwave communications. The variations of the critical frequency of the F2 layer (foF2) offer clues regarding the events happening within the entire F2 layer, and foF2 analysis is essential for stable shortwave communications. This study analyzes the seasonal and annual variations of the foF2 as well as the reactions of the F2 layer height at two locations in South Korea by employing the mean and standard deviation (SD) used in previous studies. To ensure a more elaborate analysis, the median and quartiles were used for analyzing the ionosphere. We thereby compensate for the limitations of the mean and SD in developing the SD, despite the convenience of the SD for probability analysis. The application of the median and quartiles for the analysis of ionospheric data led to analysis results with greater detail. This was achieved by determining the relative SD and concurrently displaying the outliers and range of variations

MODEL OF INSOLATION OF THE EARTH SURFACE IN THE KARA-DAG LOCALITY ACCORDING TO SSE DATA

2019 ◽  
pp. 51-58
Author(s):  
A. Volvach ◽  
G. Kurbasova
Keyword(s):  
Solar Activity ◽  
Linear Trend ◽  
Wave Model ◽  
Degree Of Approximation ◽  
Additional Research ◽  
Global Temperature ◽  
Time Frequency ◽  
The Earth ◽  
The Crimea ◽  
The Impact

Anomalous enhancement of solar insolation of the earth's surface in the presence of foci of excitation in its depths can cause a response at local sites. Such foci include, first of all, recent and past (retro) volcanoes, such as the ancient volcano on the territory of Kara-Dag in the Crimea. The authors of this article have found increased, in comparison with other localities of the Crimea, general insolation according to SSE. According to the 22-year linear trend, the rate of insolation growth falling on the earth's surface at Kara-Dag has been calculated, which is 2,69 kWh/m2 per century, being more than 2 times higher than insolation growth in other areas of the Crimea. This phenomenon has been the subject of discussion, and additional research is needed, both on the geological structure of Kara-Dag and on the impact of external and internal forces. At the stage of studying the structure of data on insolation of the earth's surface at Kara-Dag, we have built a 6-order sine-wave model. The most powerful (amplitudes more than an order of magnitude higher than the noise level) regular oscillations on the 22-year interval have periods of 365,3 and 365,7 days. Statistical estimates of the degree of approximation by a sinusoidal model (R2 = 0,9, RMSE = 0,7) indicate that, in addition to regular periodic oscillations, there are irregular fluctuations in the data at time intervals determined by a continuous time-frequency wavelet analysis. The wavelet transformation graph highlights the interval of insolation energy growth at Kara-Dag locality after 1995. In order to analyze the statistical relationship of changes in local insolation of the Earth's surface with the Earth's rotation around the axis and its orbital movement, solar activity and global temperature, autoregression models of the power spectral density were calculated using which coherent oscillations were found between variations in Kara-Dag paragraph and variations in the data: on the length of the day (LOD) with a period of 11,8 years and a square modulus of coherence of 0,85; about solar activity with periods of 10,5, 3,6 years and a squared coherence modulus of 0,8 and 0,85; about global temperature indices with periods of 2,3, 3,5 years and squares of coherence modulus 0,7 and 0,9, respectively. The increased growth of insolation and the temperature of the earth at Kara-Dag locality that we found requires additional research and observations.

Influence of thermospheric effects of solar activity on the middle atmosphere circulation and stationary planetary waves

2020 ◽  
Author(s):  
Andrey Koval ◽  
Nikolai Gavrilov ◽  
Alexander Pogoreltsev ◽  
Nikita Shevchuk
Keyword(s):  
Solar Activity ◽  
Atmospheric Circulation ◽  
General Circulation ◽  
Large Scale ◽  
Middle Atmosphere ◽  
Thermal Structure ◽  
Planetary Waves ◽  
Boreal Winter ◽  
Zonal Wavenumber ◽  
The Mean

<p>Atmospheric large-scale disturbances, for instance planetary waves, play a significant role in atmospheric general circulation, influencing its dynamical and thermal conditions. Solar activity may influence the mean temperature at altitudes above 100 km and alter conditions of wave propagation and reflection in the thermosphere. Using numerical simulations of the general atmospheric circulation during boreal winter, statistically confident evidences are obtained for the first time, demonstrating that changes in the solar activity (SA) in the thermosphere at heights above 100 km can influence propagation and reflection conditions for stationary planetary waves (SPWs) and can modify the middle atmosphere circulation below 100 km. A numerical mechanistic model simulating  atmospheric circulation and SPWs at heights 0 – 300 km is used. To achieve sufficient statistical confidence, 80 pairs of 15-day intervals were extracted from an ensemble of 16 pairs of model runs corresponding to low and high SA. Results averaged over these intervals show that impacts of SA above 100 km change the mean zonal wind and temperature up to 10% at altitudes below 100 km. The statistically confident changes in SPW amplitudes due to SA impacts above 100 km reach up to 50% in the thermosphere and 10 – 15% in the middle atmosphere depending on zonal wavenumber. Changes in wave amplitudes correspond to variations of the EP-flux and may alter dynamical and thermal SPW impacts on the mean wind and temperature. Thus, variable conditions of SPW propagation and reflection at thermospheric altitudes may influence the middle atmosphere circulation, thermal structure and planetary waves at different altitudes.</p>

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